Diluter-demand pressure breathing oxygen valve



July 25, 1950 s, SCOTT 2,516,151

DILUTER-DEMAND PRESSURE BREATHING OXYGEN VALVE Filed Feb. 5, 1947Inventor Kenneth '5. $00

Patented July 25, 1950 DILUTER D EMAND PEtE S SURE "BREATHING OXYGENVALVE Kenneth S. Scott, United StatesNavy Application February 5, 1947,Serial'No. 726,507

{Granted under the act of March 3, 1883,a;s amended -April 30, 1928; 3700. G. 757) 3 Claims.

"This invention :relates to improvements in oxygen mask valves of thedemand'type.

An object of this invention is to iprovidea'device which-gives a valveof the demand type of oxygen delivery without appreciable -negativelpressur'e requirements.

, Another object of "this =-invention is to provide a valve that willgive a *varying'dilution of oxygen with air at various altitudes;providing lesser =-amounts of oxygen and greater amounts of :air

atlower altitudesandconversely, reateramounts :of oxygen-andlesseramounts of air at higher :altitudes, up to altitudes that require pureoxy- :gen.

'A :further object-of this invention is to provide a valve for'-'anoxygen -mask that is small, :light, and compact and is primarilywithout spring action in order that it maybe madeintegral with'the'oxygen mask-or may beused-as an ac" cessory apparatus conneoted to amask :by tubing 'or the like.

' Other obiects =and advantagesvof "this invention will-become apparentas the discussion proceeds and is considered': in-'connection"with :theaccompanying claims and-drawing,- wherein like-"characters of referencedesignate like parts-throughout and wherein:

The figure in th-e drawing is a cross-section'al view of the valve:embodied in this invention,

"showing' the valve as an integrallpart of an oxy- "gen -mask.

:Referring now to the drawing, whereinfor the purpose of illustration isshown a preferred embodiment of this -=in-vention,- and Wher'einlikecharacters of reference designate like .-:parts throughout, the numeral3 designates the-case or facepiece of a conventional oxygen maskef the-type=adapted-for use in flying at high-altitudes, having-anexhaustvalveormort 4. Carried by the-mask 3 is a caseh-ofthe valveembodiedin thisinventionheldinplace in the -mask by lips lor tongues 6.Ihe case 'Smay-beof any sizeor configuration desired and by its wallsformsa cavity or chamber 1. An-inlet tube or pipe t is -connected to anoxygen "tank lnot-shown). A second inlet :9 communicates withthe-outsideflair and permits-passage of air into the chamberl. After theair and oxygen is mixed, eiihaust there of from the valve is prov'idedfor by means of a ,passage it, which in turn communicates With'theinside ofthe mask't. A tubular sleeve orstandpipe 'l'lis rigidly affixedto and depends inwardly from thebottom wall (readingthe=drawingfromleftto right, the right side-is designated as "the ibotto'm) of the tures Itin the standpipe l I. stream ends 25, of the venturi 28 are affixed toor are made integral with the inside wall it of case in-to the chamber7. Communication between the standpipeil and the oxygen intake Br-isprovided for 'by means of a nipple or other connection 12. The end orinside terminus of the standpipe l l is completely closed, inanysuitable manner, as by-a cap 113. Disposed circumferentially betweenthe cap 13 and the bottom of the standpipe is a plurality of aperturesor =ho1es i l. The size and spacing of the said holes dd will dependupon the-specificdesign of each valve, as the total area of the "holeswill lim-it the maximum volume of oxygen that enters the valve.

HAtubular sliding sleeve valve ifi extendsover thestandpipe i has shown.The saidsleeve valve 55 "is constructed With-an inside wall it and anoutside wall H which form between them aJchamher-I8, closed at its lowerterminus l9. Aplurality of venturi 263 are .provided, circumfer--.entia1ly-of the valve i5, and extend through the chamber l8, :asshown, and are ,placed substantiallyadjacent-to and coaet with the holesoraper- The inside, or up the sleeve E5, the throat or low pressureportion '22 of each venturi is disposed within the chamber 18, and theoutside, or downstream end 23,

of each venturi isaflixed to or made integral with the outside wall llof the sleeve is, as shown. 'The throat or low .pressureportion 22. ofeach venturi is provided with apertures 24 which communicate-with thechamber it. 'A movableiplate "25 carries the upper end of the sleevevalvev l5 and is provided with a centraliy'located opening "26 which.forms, in itself, a valve seat andco-mmunicates with the chamber it ofthe valve 15, as shown. -A sprin -loaded or one-way valve 21, having aspring 23, is carried by a lip or bridge mgprovide'd as shown,in'thechamber it of the s'leeve'valve 55. The plate is carried byraresilientcase or bellows 3, as shown, and the combination of theplateand bellows form a chamber 3i, which communicates with the outlets 23aneroid. A tube 36 terminates at one end 36a in open communicationwithin the chamber of the aneroid 32, and the opposite end of the tube 336b terminates in the atmosphere. A valve 31, operated either manuallyor automatically, is provided in the tube 36, as shown. The plate 34 ofthe pressure breathing aneroid 32 is rigidly aflixed to the plate 25 byan open bridge 38, as shown.

Within the bridge structure proper is a second air-diluting aneroid 39,carried by the plate 34 of the aneroid 32. Bellows 39a and a closureplate 40 complete the closure of the air-diluting aneroid 39. Afiixed toand carried by the closure plate 40 is a tubular valve 41 whichsurrounds the seat opening 25 and seats on an annular seat 42 providedon the plate 25, as shown.

In operation, either high or low pressure oxygen is delivered to thestandpipe H and when the sliding sleeve i5 is moved into a positionwhere the upstream Venturi intakes 2| are opposite the openings [4 ofthe standpipe ll, oxygen passes through each venturi into the chamber31. The low pressure across the throat of the venturi draws air from thechamber l8 through the holes or apertures 24, where it is mixed with theoxygen and thence enters the chamber 3!. The air-oxygen mixture thenpasses into the mask 5 by means of the passage I!) where it is breathedin the conventional manner and expelled through the exhaust valve Airenters the valve 5 through openings 9 and passes into the chamber 1thence goes through the bridge structure 38, under the tubular valve 4|,past the valve seat opening 23 and into the chamber l8, thence throughthe venturi throat openings 24 and out the venturi as described above.taking place between the sleeve valve and the standpipe H; however, thiswill be in such small amounts and will vent itself into the chamber 3|where it ultimately will be used. To prevent a loading caused by anyaccumulation of oxygen that may occur between the sleeve and the top ofthe standpipe, a vent 43 is provided in the upper portion of the sleevel5, as shown.

The normal position of the valve I5 is closed, with the venturi raisedabove the opening it. During inhalation, the plate 215 is pulleddownwardly, because of the reduction in pressure in the mask. As thiscover plate '25 moves downward, the sleeve [5 is brought down, and theventuri 20 and the holes M coincide. Oxygen then flows through theventuri until a positive pressure is built up within the mask andconsequently within the chamber 3! which urges the plate 25 upward, thismoving the venturi away from the holes M. It is to be here noted that nopressure is developed toward opening or closing the sleeve valve l5except by the negative or positive pressure of breathing.

The pressure breathing aneroid is designed so that at approximately35,000 feet or at any other desired altitude, the valve 31 would beclosed, thus sealing the chamber of the aneroid 32 so that the chamberexpands with increasing altitude and because of the connection by thebridge 38, puts pressure on the plate 25, causing the oxygen sleevevalve to progressively remain open at increased altitudes and to remainopen except when the mask pressure is above atmospheric pressure at thataltitude.

The air-diluting aneroid 3B is preferably sealed at any desired pressurebefore assembly in the valve. The pressure at which this aneroid issealed depends upon the specific design of each valve and the altitudeat which the aneroid is intended to function; however, adjustable meansThere will be some leakage of oxygen P (not shown) may be provided tovary the seal pressure of the aneroid 39. As the atmospheric pressure inthe chamber 1 decreases, the aneroid 39 expands and urges the plate 40downwardly, causing the tube valve 4] to gradually close on the seat 42.With proper setting of this airdiluting aneroid 39, the valve will closeat altitudes demanding pure oxygen, with less and less air admitted asthe completely closed position is approached.

It is to be understood that the form of this invention, herewith shownand described, is to be taken as a preferred example of the same, andthat various changes in size, shape and arrangement of parts may beresorted to without departing from the spirit of this invention, or thescope of the subjoined claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is:

l. A unitized pressure breathing oxygen valve comprising a housinghaving a chamber therein, air inlet means communicating with saidchamber, a variable volumetric chamber within the first-mentionedchamber consisting of a bellows carrying a movable plate, anOxygen-inlet valve in the said variable chamber actuated by the saidplate, oxygen inlet means communicating with said valve, air inlet meanscarried by the said plate communicating with the said oxygenvalve,oxygen-air outlet means communicating with said variable chamber, apressure breathing aneroid in the said housing chamber coacting with theaforesaid plate, an air-diluting aneroid, and a valve carried by thesaid air-diluting aneroid coacting with the said air inlet means carriedby the said plate.

2. A diluter demand type pressure breathing oxygen regulator comprisinga housing having a chamber therein, air inlet means communicating withsaid chamber, a plate carried by a resilient member within the saidchamber, said rigid plate and resilient member forming a variablevolumetric chamber within the first-mentioned chamber, oxygen inletmeans in said variable chamber having holes therein, a sliding valvemember carried by the said rigid plate and in sliding engagement withthe said oxygen inlet means, venturi disposed circumferentially aboutthe said sliding valve member coacting with the holes in said oxygeninlet means, air inlet means in the said rigid plate communicating withthe said sliding valve member, an aneroid carried within the chamber ofsaid housing adapted to regulate the sensitivity of the said variablevolumetric chamber, and a second aneroid carried by the first-mentionedaneroid having an air regulating means coacting with the said air inletmeans in the rigid plate.

3. A diluter demand type pressure breathing oxygen regulator comprisinga housing having a chamber therein, air inlet means communicating withsaid chamber, a tubular bellows havin a movable plate carried upon oneend and being affixed to the housing at the other end forming anairtight variable volumetric chamber within the first-mentioned chamber,air inlet means in said movable plate, an oxygen air outletcommunicating with said variable chamber, a tubular standpipe withinsaid variable chamber having a plurality of holes disposed circumferen-'inlet'eommunicating with said standpipe, a tubu .larrsliding sleevevalv+having inner and outer walls forming a chamber therebetween closed'at one end and communicating with the air inlet means of said platea't' ithe opposite end slidably mounted on the saidstandpipe and carriedby the said movable plate; a one way valve coating between the hole insaid movable plate and the said chamber of theslidlng sleeve, venturi'dis'- posed circumferentially about said tubular sleeve valve coactingwith the holes in said standpip'e, apertures in the throats of the saidventuri adapted to admit air i'rom the chamber of "the said slidingsleeve valve, an aneroid carrledby the said housing located within thefirst-mentioned chamber, communicating means connecting the said aneroidwith the atmosphere, means connecting the said aneroid with the above-REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date Meidenbauer Feb. 24, 1948 NumberCertificate of Correction Patent N 0. 2,516,151 July 25, 1950 and thatthe said Letters Patent should be read as corrected above, so that thesame may conform to the record of the case in the Patent Oflice.

Signed and sealed this 21st day of November, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Uommz'ssz'oner of Patents.

